A voice mail system accepts voice messages from many subscribers, stores the messages, permits further processing and is able to repeat the messages verbatim.
Each subscriber wishing to use such a voice mail system has a voice box with an associated box number installed. In this way, any subscriber entering this box number can leave a voice message, which the owner of the box can retrieve at any time, process it further (e.g. append a comment) and pass it on. Access is only possible by means of a password (e.g. entering a multiple digit number) known to the box owner, so that only an authorized box owner is able to access his voice box to retrieve and possibly change the voice messages.
Any telephone subscriber can access such a voice mail system via the telephone network by means of an access number assigned to the system, and leave messages for voice box owners, whereby voice output guides the user ("SEL-voice mail system for the public telephone network", company brochure from Standard Elektrik Lorenz AG, Stuttgart).
Furthermore, voice mail systems are known, which can also process text messages, as well as voice and text combinations ("MEZZA, Voice and Text Integration in the Office", Office & Information Management International, February 1989, pages 16 to 17).
Since, on the one hand, any number of subscribers have access to such voice mail systems, but on the other, each voice mail system only has a finite number of access lines (e.g. 64), it can often happen that access for leaving a message or for retrieving it, is not available.
Although the number of access lines in a system could be increased, it would slow the system down significantly because of the greater flood of information. This would entail higher costs for the subscribers due to the longer line utilization time, and finally cause a reduction of the total capacity.
The invention has the task of producing a system that makes a significantly higher traffic load possible, so that subscribers are able to leave a message for a box owner, or a box owner can retrieve his messages, during a particularly critical time of the day.
In addition, a method must be provided for leaving messages in a message box in such a system, and a method for retrieving or leaving messages by a message box owner in such a system.